Dental vulcanizing apparatus



(No Model.) I

J. HOOD & S. H. REYNOLDS. DENTAL VULGANIZING APPARATUS.

- 1 Io.334,52.9. Patented Jan. 19, i1886. l1 5 1 3 9 k F 2 t 1 1.

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PATENT OFFICE.

JOHNYHOOD Am; STEPHEN ELREYNO'LDS, OF BOSTON, MASSACHUSETTS.

QDENTAL V UL CANIZlNG APPARATUS.

- UPECEFICATIONformingpart of Letters Patent No. 334,529, dated January 1 1886- Application filed May 15, 18%. Serial No. 165,551. (No model.)

To (ZZZ whom it may concern:

Be it known'that we, Joan H001) and STEPHEN H.REYNOLDS, citizens of the United States, residing, atBoston, in the county of Suffolk and State cf Massachusettahave invented certain new and useful Improvements in Dental Vulcanizing Apparatus, of which the following is a specification, reference being had therein to the accompanying drawro ings.

This invention relates to an improvement in that class of vulcanizing apparatus em ployed by dentistsin the manufacture of plates for holding artificial teeth. Heretofore these machineshave been so constructed that much time was lost in properly securing the removable head or cover by which one end of the cavity designed to receive the articles tobe vulcanized was closed" In order to appreciate 20 this difficulty, it is only necessary to state that the heat required to produce the desired change in the caoutchouc plate is not less than 275 Fahrenheit, indicating a steam-pressure of forty-five pounds to the square inch, or

about five hundred and forty pounds on the cover of an ordinary vulcan'izer for dental purposes. In order to withstand this pressure, it n has been common to secure these heads in place by means of a series of bolts passed through a g flange attached to the body of the vulcanizer and through the head or cover. Another method has been to employ stirrups provided with one or more screw-bolts, which, after the I stirrup was placed in position, were screwed 3 5 up against the head after the insertion of a suitable packing between it and the body of the vulcanizer. Although these devices were successful in the matter of holding the head in position against the steam-pressure, they were 40 defective in the loss of time required to arrange and screw up and unscrew the fastening devices. Another defect in the apparatus commonly used is the lackof an efficient and cheaply-constructed safety valve or device for relieving the pot or body of the vulcanizer from overpressure.

The object of ourinvention is therefore to provide a perfectly-reliable fastening for these covers which shall be capable of quick adjustment, thus overcoming the delay caused by the use of the devices ordinarily employed; and, further, to provide the steam-waste cock at- .tached to the cover with a safety device, which shallyeffectually prevent an excessive or dangerous pressure of steam from accumulating in I the body of the apparatus.

Ourinvention therefore consists in the employ ment ofan eccentric or cam provided with an operating-lever, said cam being reniovably journaled in ears which project beyond the open end and from each side of the body of the vulcanizer, the cover being provided with a raised stiffening-rib crossing its outer surface diametricallyto receive the pressure of the cam; and, further, it consists in the use, in connection with the steam-escape cock attached to the cover or other part of the apparatus, of a safety disk made of fracturable material, which, should the pressure within the apparatus become excessive, will burst and allow the steam to escape.

In the drawings, Figure l is a side view of the apparatus with the cover in place as in use. Fig. 2 is a longitudinal section through the body, cover, and ears for holding the cam. Fig. 3isa diametrical section of thering which surrounds the open end of the body, showing.

one of the cam-holding ears. Fig. ais an end view of the cam and its operating-lever. Fig. 5 is an end view of the same. Fig. 6 isalongitudinal section through the steam cock, showing the construction of the same and location of the safety-disk.

The body'or pot A of this vulcauizer is formed of metal having sufficient thickness to give it the needed strength, and is provided at its open end with an enlargement, a, which completely encircles this open end and forms a projection, over which the cover B fits. Said projection also forms an abutment, against which the eancarrying ring 0 has its bearings. The opening in this ring is of such size as to allow the body A to pass through until the projection a is reached, against which it has a bearing entirely around the body. Diametrically oppositeito each other, and attached to the ring 0, or forming an integral part thereof, are the ears E E, each of which is provided with a circular headed recess, 1). These recesses do not open upon the same side of the ears E Egbut upon opposite sides, so that when the cam D is to be inserted therein or withdrawn therefrom a twisting motion must be given to the same. The cover B is provided with an annular channel, 0, within its rim,which receives andholds such packing as may be required to form the joint between said cover and the open end of the body. Upon the outer side of the cover, and crossing it, is a series of flat-topped elevations, d, which may either form an integral part of the cover or may be added to it. These elevations stiffen the cover and form the bearings for the cam D, which, when in use, extends across the outside of said cover, and engages, by means of its journals 6 e, with the recesses b in the ears E. This cam is also provided with a handle or lever, F, by means of which it is operated, so that when the cover, is in place on the open end of the body, and the journals of the cam engage with the ears E, raising the lever to a vertical position will cause the cam to release the cover, so as to allow of its removal, while depressing said lever will cause the cam to force the cover down upon the open end of the body, causing said end to enterthe recess 0, and, with the aid of the packing inclosed therein, form a perfectly steam-tight joint between the two, the time occupied in making or releasing this joint, it will be seen by the above description of the construction and operation of the apparatus, being only that needed to raise or depress the canrlever, as this movement of said lever accomplishes the same result as is accomplished by the manipulation of the screw-bolts in the ordinary way.

Ratchet-teeth n are formed in or upon one or both ends of the cam D, and a pawl, a, is attached to one or both ears E, which engages said ratchet and holds the cam in place.

The cover 13 is provided with a thermon1eter, H, by which the temperature of the inclosed steam can be determined, and also its pressure; but to insure safety in the use of the apparatus, the steam-cock G is provided with a safety-disk, t. This disk is formed of any suitable material that is not affected by moisture, but will give way whenever the pressure within the apparatus reaches a certain prede- This disk is secured upon termined limit.

the end of the cock over thelongitudinal opening through the same by means of the screwcap f. Should the disk be fractured and allow the steam to escape, by turning the plug 9 its L egress may be arrested, and when it is desired to blow off the steam at the close of an operation, or at any other time, it may be effected by turning the plug 9 into such a position that the orifice through it shall connect the longitudinal opening through the cock with another formed in the enlarged or bulbous part of the same.

It will be apparent that the ring O might be cast with the body A, forming an integral part thereof, if the body is made of cast metal; but we prefer to make the body of copper, as having great tenacity, and being an excellent conductor of heat, the ring and other parts being cast metal, and held in place upon the body by rivets or other suitable means.

Having thus described our invention, we claim as new, and desire to secure by Letters Patent, the following:

1. In a vulcanizing apparatus, the body A, ring O, and cover B, provided with packingreeess c and elevations d, in combination with the cam D, having ratchet-teeth a, and pawl a, attached to the ears of ring O, arranged and operating as described.

2. In a vulcanizing apparatus, the combi nation of the body A, having circumferential projection a, the coverB, having annularpacking-recess c on its under side, and a series of flat-topped elevations, d, on its upper side, the ring 0, provided with recessed ears E, the cam D, having ratchet-teeth n, and provided with journals 6, for engaging the recesses in said ears, and the pawl n, attached to one of said cars, all as shown and described. 85

In testimony whereof we hereunto affix our signatures in presence of two witnesses.

JOHN HOOD. STEPHEN H. REYNOLDS. Vitnesses:

JOHN llIAY, FRANK D. Hown. 

